Dual steerable vehicle

ABSTRACT

A tricycle may be operable between a first mode of operation steerable by a tricycle rider, and a second mode of operation steerable by an individual pushing the tricycle. In both such first and second modes, the frame of the tricycle is configured to rotatably support the rear wheels and configured to support the head tube at a distance from the rear wheels such that a distance between the head tube and rear wheels need not necessarily be changed even when the front wheel axis location is changed from one mode to another.

This application is a continuation of U.S. patent application Ser. No.13/919,389, filed Jun. 17, 2013, now pending, which is a continuation ofU.S. patent application Ser. No. 13/569,582, filed Aug. 8, 2012, nowU.S. Pat. No. 8,465,037, which claims priority to U.S. ProvisionalApplication No. 61/523,215, filed Aug. 12, 2011, the entire contents ofeach which are incorporated herein by reference.

TECHNICAL FIELD

The invention generally relates to the field of riding vehicles.

BACKGROUND

Whether used for transportation or recreation, tricycles may be used forriders of different sizes and capabilities. Some tricycles areconfigured to be propelled and steered by the rider. In some instances,tricycles are configured to be pushed from behind, by an individual,such as an adult pushing a child. Typically, when the tricycle ispropelled by the rider, the rider uses the pedals attached to the frontwheel and steers the tricycle using a handle which is typicallyconnected to the front wheel. Tricycles configured to be pushed frombehind sometimes include a mechanical steering mechanism to permit anadult walking behind the tricycle to mechanically turn the front wheel.

SUMMARY

An exemplary embodiment of the invention may include a tricycle operablebetween a first mode of operation steerable by a tricycle rider, and asecond mode of operation steerable by an individual pushing thetricycle. In both such first and second modes, the frame of the tricycleis configured to rotatably support the rear wheels and configured tosupport the head tube at a fixed, non-adjustable distance from the rearwheels. That is, the distance between the head tube and the rear wheelsneed not necessarily be changed even when the front wheel axis locationis changed from one mode to another.

More specifically, a tricycle may include a fork having at least oneblade configured to support a front wheel in a manner permitting thefront wheel to rotate about a front wheel axis. A stem may be configuredto rotatably extend from the head tube and a rider handle, may beconfigured to turn the fork about a stem axis transverse to the frontwheel axis, the rider handle, in the first mode, being configured to berotationally coupled with the stem in a manner permitting a tricyclerider to exert forces on the rider handle and thereby turn the fork, andthe rider handle in the second mode, being configured to be rotationallyuncoupled from the stem, preventing forces on the rider handle fromturning the fork, wherein the stem extends from the fork at an anglechosen so that when the stem axis leads the front wheel axis the pedalsdo not necessarily interfere with the rider's feet, while turning,without a need to alter a distance between the seat and the head tube,and wherein, in the first mode, the stem extends from the fork at anangle chosen so that when the stem axis trails the front wheel axis thepedals are oriented for pedaling by a rider without a need to alter adistance between the seat and the head tube

The handle, in the first mode, may be rotationally coupled with the stemin a manner permitting a tricycle rider to exert forces on the handleand thereby turn the fork. In a second mode, the handle may berotationally uncoupled from the stem, preventing forces on the handlefrom turning the fork.

The tricycle may include a pair of rear wheels, a front wheel havingopposing sides and a front wheel axis, and a pair of pedals, where eachpedal may be configured to rotate the front wheel. The tricycle mayinclude a seat as well.

The foregoing is a summary a few exemplary features of a fewembodiments, and is not intended to be restrictive of the invention ashereinafter described and claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a side view of a tricycle, without parental handle, and whichmay be used in a first mode of operation, according to an embodiment ofthe invention.

FIG. 2 is a side view of a tricycle, having a parental handle, which maybe used in a second mode of operation, according to an embodiment of theinvention.

FIG. 3 is front view of the tricycle of FIG. 2.

FIG. 4 a is a side view of a front wheel fork and stem assemblyconsistent with an embodiment of the invention.

FIG. 4 b is a perspective view of the front wheel assembly of FIG. 4 awith mud guard added.

FIG. 5 a is a front view of a handle assembly consistent with anembodiment of the invention.

FIG. 5 b is a cross-sectional front view of a coupling assemblyconsistent with an embodiment of the invention.

FIG. 5 c is a perspective assembly view of a stem and coupling memberconsistent with an embodiment of the invention.

FIG. 6 is a cross sectional side view of a coupling member consistentwith an embodiment of the invention.

FIG. 7 is a cross-sectional side view of a coupling assembly consistentwith an embodiment of the invention.

FIG. 8 is a cross-sectional side view of another coupling assemblyconsistent with an embodiment of the invention.

FIG. 9 a is a cross-sectional side view of yet another coupling assemblyin an uncoupled position, consistent with an embodiment of theinvention.

FIG. 9 b is a cross-sectional side view of the coupling assembly of FIG.9 a in a coupled position.

FIG. 10 is a perspective view of a holding mechanism, according to oneembodiment of the invention.

FIG. 11 is a schematic diagram of a tricycle, having a swivel wheel,according to another embodiment of the invention.

FIG. 12 is a partial assembly view of the tricycle of FIG. 11;

FIG. 13 is a schematic diagram of an enlarged front tube of the tricycleof FIG. 11.

FIG. 14 is a schematic diagram of the enlarged front tube of FIG. 13with an associated interconnecting base.

FIG. 15 is an assembly view of the front wheel assembly of the tricycleof FIG. 11.

FIG. 16 is a further assembly view of the front wheel assembly of thetricycle of FIG. 11.

FIG. 17 is an assembly view of the coupling part of FIG. 16.

FIG. 18 partial cut-away view of the shaft and the coupling mechanismaccording to an embodiment of the invention.

FIG. 19 is an enlarged partial cross-sectional view of the shaft and thecoupling mechanism of FIG. 18.

FIG. 20 is a perspective view of a tricycle in its second mode,according to an embodiment of the invention.

FIG. 21 is a perspective view of a tricycle in its second mode,according to an embodiment of the invention.

FIG. 22 is an enlarged partial cross-sectional view of a front end ofthe tricycle in its second mode, according to an embodiment of theinvention.

FIG. 23 is a perspective view of a suspension mechanism, according to anembodiment of the invention.

FIG. 24 is a side view of the suspension mechanism, according to anembodiment of the invention.

FIG. 25 is a bottom view of a front wheel and its pedals, according toan embodiment of the invention.

FIG. 26 is a side view of inner parts of a suspension mechanism,according to an embodiment of the invention.

FIG. 27 is a perspective view of a portion of a front wheel assembly,according to another embodiment of the invention.

FIG. 28 is a perspective view of parts of a front wheel assembly,according to an embodiment of the invention.

FIG. 29 is another perspective view of parts of a front wheel assembly,according to an embodiment of the invention.

FIG. 30 is another perspective view of parts of the front wheelassembly, according to an embodiment of the invention.

FIG. 31 is a further perspective view of parts of the front wheelassembly, according to an embodiment of the invention.

FIG. 32 is yet another perspective view of parts the front wheelassembly, according to an embodiment of the invention.

DETAILED DESCRIPTION

The terms of “front”, “rear”, “down”, “up”, “bottom”, “upper”,“horizontal”, “vertical”, “right”, “left” or any reference to sides ordirections are used throughout the description for the sake of brevityalone and are relative terms only and not intended to require aparticular component orientation.

Embodiments of the invention may include a tricycle operable between afirst mode of operation steerable by a tricycle rider, and a second modeof operation steerable by an individual pushing the tricycle. Atricycle, as used herein, includes any vehicle with a wheel in the frontand two wheels in the rear. FIG. 1, for example, illustrates is a sideview of a tricycle, and which can be used in a first mode of operationwhere a rider may propel the tricycle using pedals 141 and 142 (see FIG.3). A second mode of operation may be accomplished when an individualbehind the tricycle, pushes the tricycle using, for example, parentalhandle 500, as illustrated in FIG. 2.

Embodiments of the invention may include a tricycle having a frame and apair of rear wheels for rotatable connection to the frame. Asillustrated in FIG. 1, exemplary tricycle 800 may include a main frame700 including head tube 707. Two rear wheels 400 (see FIG. 3) may besupported toward the rear of the main frame 700. The main frame 700 maybe made of any material or have any structure, shape, or configurationcapable of supporting a tricycle rider. For example, main frame 700 mayinclude metal tubing or any other rigid material, and may be configuredto support a seat 600.

In one embodiment, the rear wheels 400 may be rotatably supported on acentral axle (the support shaft 702 of which is illustrated in FIG. 3)which may be inserted into the rear part of the main frame 700,effectively allowing the rear wheels 400 to rotate frontwards orbackwards. A seat 600 may be connected, by any known method, to the mainframe 700. The seat may have any configuration capable of supporting arider. It may include or omit a back rest, may be integrally formed orformed of multiple materials, and/or may be uncovered or covered incloth, fabric, or other material.

The main frame 700 may also have a number of connection options for seat600, effectively allowing the placing/adjustment of seat 600 at a numberof locations along the main frame 700. In one embodiment, a basket 410may be added and placed on the rear part of main frame 700 between therear wheels 400.

FIG. 2 is similar to FIG. 1, adding a parental handle, which may bepermanent, semi-permanent (e.g., removable with tools), or designed tobe removable at will. The term “parental handle” as used herein,includes any structure, regardless of shape or material that may begrasped by an individual behind a tricycle and used to propel thetricycle from behind. By way of example, parental handle 500 illustratedin FIG. 2, may be made of one or more metal pipes or from any otherrigid material. In one embodiment, the parental handle 500 may betelescopically adjustable to accommodate the height of the individualpushing the tricycle 810. The adjustable height mechanism of parentalhandle 500 may belong to any of the known adjusting techniques such asby a popup pin held within the inner pipe of the handle and which popsout of one of the holes of the outer pipe, where the pin may be pushedfrom one hole and popped out of a different hole, for adjusting theheight of the handle.

Embodiments of the invention may also include a front wheel havingopposing sides and a front wheel axis. For example, and as illustratedin FIG. 3, front wheel 100 includes first side 102 and opposing secondside 104. The wheel 100, as illustrated in FIG. 4 b, includes a centralaxis c at its midpoint 303, about which the wheel 100 is rotatable.

Similarly, embodiments of the invention may include a pair of pedals,each pedal configured to rotate the front wheel. Numerous types of pedalmay be employed constant with embodiments of the invention. Such pedalsmay include fixed pedals, removable pedals, foldable pedals, or pedalsthat flip up, retract, or have an otherwise alterable configuration.Thus, as used herein, the term pedal refers to any structure thatpermits a rider to propel a tricycle using foot power. An example ofpedals, consistent with embodiments of the invention, include pedals 141and 142 (see, e.g., FIG. 3). In addition, a pedal may be configured torotate the front wheel a portion of the time (e.g., during the firstmode when the rider propels the tricycle, and may be removable from,disengagable from, folded onto, or otherwise deactivatable during asecond portion of the time (e.g., during the second mode when a parentpushes the tricycle from behind).

Each of pedals 141 and 142 may be connected to the center of the frontwheel 100, via pedal rod 140. The pedal rod may be continuous andconnected to both pedals, or the pedal rod 140 may be configured of twoindependent sections, each connected to a separate one of the pedals 141and 142. In a first mode of operation, the propelling factor of pedalrod 140 may be connected, by any mechanical interconnection means, to arotating factor of the front wheel 100, thereby allowing rotation of thefront wheel 100 using pedal rod 140. By rotating the pedal rod 140, thefront wheel 100 may be rotated about its center axis, i.e. about themiddle part of pedal rod 140 which may act as the front wheel 100 axle.Alternatively, the front wheel may have a separate axle to which one ora pair of pedal rods connects.

Pedal rod 140 may include three parts; a middle part located at a centerof the wheel 100 and used, among others, as an axle of wheel 100, a leftside for connection to a left pedal, and a right side for connection toa right pedal such as pedal 141.

Embodiments of the invention may include at least one blade configuredto support the front wheel in a manner permitting the front wheel torotate about the front wheel axis. As used herein, the term “blade”includes any structure capable of supporting the front wheel in arotatable manner. A wheel may be supported, for example, on a singleblade or on a pair of blades. FIG. 4 a illustrates an example of a blade130 used to rotatably support wheel 100. FIG. 3 illustrates wheel 100supported by a pair of blades 130 and 131. When a pair of blades areemployed, they are typically interconnected at upper ends oppositepoints at which they interconnect to the wheel axis and are collectivelyreferred to as a fork (although, as used herein, the term fork may alsoinclude structures that have just one blade.) Thus, in various figures,a fork is generally designated with the reference numeral 130. The forkmay be formed of individual blades that curve toward each other, or,interconnecting structure may join two individual fork blades.

The middle part of pedal rod 140 may be pivotally held by the opposingdistal ends of fork blades 130 and 131 in a manner such that the frontwheel is capable of rotating about its center axis. A mud guard 301 maybe disposed near a top of the fork 133, opposite distal ends supportingthe wheel.

Embodiments of the invention may also include a stem configured toextend from the head tube in a manner permitting the stem to rotate(i.e., rotatably connectable to the frame). A stem may be any structureconnectable to the fork and that is capable of conveying a turning forceto the fork and/or that supports the fork in a rotatable manner. Forexample, FIG. 4 a illustrates stem 305 that extends from fork 133. Thus,when either the fork 133 or the stem 305 rotates, the other may rotatewith it. The stem may be rotatably connected to the frame 700 via theframe's head tube 707. The frame's head tube 707 may be a part of theframe 700, wielded to frame 700, or connected to frame 700 by any othermeans such as bonding, screws, threading, or any other mechanismpermitting connection of a head tube to a frame.

In some exemplary embodiments, it may be beneficial to employ a stemgeometry that facilitates dual mode operation. For example, the maximumwidth of the front wheel (e.g., proximate the tread of the wheel) may beat least three times greater than the minimum diameter of the fork'sstem. This configuration can lower turning friction, facilitatingcontrol from behind during the second mode of operation. In anotherembodiment, the stem may include a rod that has a minimum diameter thatis at least four times smaller than an average width of the front wheel.The rod may have any structure that permits rotation, and may have asolid, hollow, or semi-solid. For example, the rod may be constructed ofmetal or other rigid material. The stem may be comprised of sectionshaving varying diameters. In the above examples, a smallest or “minimum”diameter may be of particular interest, especially if that minimumdiameter is at a rotational stem connection.

For example, when the front wheel maximum width is about 50 mm, the stemmay have a minimum diameter of between about 6 mm and 12 mm, or less.When the front wheel maximum width is 55 mm, for example, the stem mayhave a minimum diameter of about 13 mm and 18 mm, or less. All elsebeing equal, a narrower diameter stem facilitates greater steeringcontrol when the tricycle is pushed from behind. Thus, consistent withembodiments of the invention, the stem diameter may be less than onequarter the maximum front wheel width. By way of additional examples,when the front wheel maximum width is in a range of 45 to 55 mm, thestem may have a minimum diameter of 9 to 18 mm. For example, when thefront wheel maximum width is in a range of 20 to 60 mm, the stem mayhave a minimum diameter of 4 to 15 mm.

The stem's minimum diameter may be greater than one third the maximumwidth of the front wheel, and the invention, in its broadest sense isnot limited to any particular dimension.

Regardless of the dimensions of the stem, it may be held by a bearingwhich may reduce turning friction and facilitate the second modeoperation and the first mode of operation as well.

As illustrated, for example in FIG. 4 a, stem 305 may have a centralaxis a, and fork 133 may have a fork axis b and the stem 305 may beconnected to the fork 133 in a manner such that the central axes a and bform an obtuse angle x there between. Angle x may be, for example, equalto or less than about 179° degrees. In some embodiments, angle x may bebetween about 170°-174°. In another embodiment the angle x may bebetween about 165°-179°. In a further embodiment the angle x may bebetween about 165°-173°. In yet another embodiment, the angle x may bebetween about 170°-175°. As the angle x approaches 180°, an ability tocontrol steering from behind in the second mode of operation may befacilitated by a minimum stem diameter of three to four times smallerthan the maximum width of the front wheel. Thus, when the angle x isbetween 165°-479°, a stem with a minimum diameter of three to four timessmaller than a maximum width of the front wheel may be desirable. Forexample, as illustrated in FIG. 4 b, width w of front wheel 100 may beat least three to four times greater than the diameter d of stem 305.For example, when the front wheel width w is in a range of 25 to 51 mm,the stem may have a minimum diameter d of 6 to 12 mm. For example, whenthe front wheel width w is in a range of 45 to 55 mm, the stem may havea minimum diameter d of 9 to 11 mm. For example, when the front wheelwidth w is in a range of 20 to 60 mm, the stem may have a minimumdiameter d of 4 to 15 mm. In one embodiment the average diameter of thestem is at least three times smaller than the average width of the frontwheel. For example, when the front wheel average width w is in a rangeof 45 to 55 mm, the stem may have an average diameter d of 9 to 11 mm.For example, when the average front wheel width w is in a range of 20 to60 mm, the stem may have an average diameter d of 4 to 15 mm. In oneembodiment, the maximum width of the front wheel may be at least threetimes greater than the maximum diameter of the fork's stem. For example,when the front wheel maximum width is in a range of 45 to 55 mm, thestem may have a maximum diameter of 8 to 15 mm. For example, when themaximum front wheel width w is in a range of 20 to 60 mm, the stem mayhave a maximum diameter d of 4 to 15 mm.

In embodiments of the invention, the stem axis may extend in a directiontransverse to the front wheel axis. As illustrated in FIG. 4 b, forexample, the central axis a of stem 305 extends in a directiontransverse to (i.e., extends in a differing direction) and is offsetfrom rotational axis c of front wheel 100 by a distance y. In oneembodiment, the minimal distance y may be no more than about 50 mm. Inanother embodiment, the offset distance y is in the range of betweenabout 18 mm and 25 mm. In yet another embodiment, offset distance y isin a range of about 15 mm and 40 mm. As the offset distance decreaseswith all else equal, so to decreases an ability to turn the tricyclefrom behind using parental handle 500. Thus, in one embodiment, when theoffset distance is between 15 mm and 22 mm, the angle x between the stemand the fork is between about 7 and 10 degrees, and the minimum diameterd of the stem 305 is at least three times less than the width w of thefront wheel. This combination of geometries is exemplary of aconfiguration that may permit a parent to steer, in the second mode,when the stem axis a leads the wheel axis c, or may permit the tricyclerider to steer, in the first mode, when the wheel axis c leads the stemaxis a, as will be discussed later in greater detail.

In one embodiment the fork axis a is designed to lead the front wheelaxis c in the second mode of parental steering control. The leading stemaxis in such instances positions the pedals further rearward than theywould ordinarily be if the stem axis a trailed the wheel axis c, e.g. asin the first mode, potentially giving rise to a concern that the pedalsmay be too close to the rider for comfort. However, by employing aminimal angle x between the fork and the stem, peddles 141 and 142 maybe maintained at a sufficient and comfortable distance from the riderwithout necessarily having to adjust the rider's position rearward, suchas might occur with an adjustable frame (although adjustable frames maybe used together with all embodiments of the invention). Thus, the frame700 may be configured to maintain a fixed, non-adjustable distancebetween the fork stem and the rear wheels. This can occur, for exampleby constructing the frame 700 from a fixed length, non-adjustable pieceof material. Alternatively, the frame may be constructed of multiplepieces in a manner that does not necessarily require adjustment of theframe length during use.

In one embodiment, the shortest distance between the front wheel centerand the imaginary line of the stem axis is between 10 mm-30 mm. Inanother embodiment, the shortest distance between the front wheel centerand the imaginary line of the stem axis is between 15 mm-25 mm. In yetanother embodiment, the front wheel axis is designed to trail the stemaxis in the second mode of operation. The figure though is non-limitingand alternatives may be employed, consistent with principles of theinvention described herein.

In one embodiment the maximum width of the front wheel is at least threetimes greater than the minimum diameter of the fork's stem.

Embodiments of the invention may further include a rider handle,configured to turn the fork about a stem axis transverse to the frontwheel axis. As used herein, the term “rider handle” is used broadly torefer to any structure, regardless of shape, material, or size, that canbe grasped by a tricycle rider and used to turn the front wheel. Forexample the rider handle may be in the form of a handlebar, with acurved rod-like shape, or a straight rod-like shape. Alternatively, therider handle may be in the form of a steering wheel or other closed oropened loop structure capable of manipulation by a rider. The riderhandle may have a solid or open core. Like other parts of the tricycle,the rider handle may be made of any material or combination ofmaterials.

The rider handle may be configured to turn the fork via a mechanicalinterconnection with, for example, either the fork or the stem. Themechanical interconnection may be direct or may include intermediateparts through which forces may be transferred via the rider handle tothe front wheel.

By way of example only, a rider handle may include handlebar assembly200 illustrated in FIGS. 1 and 2. As illustrated in greater detail inFIG. 5 a, rider handle assembly 200 may include a handlebar 115, an arm201, and a coupling mechanism 202.

The rider handle, in a first mode, may be configured to be rotationallycoupled with the stem in a manner permitting a tricycle rider to exertforces on the rider handle and thereby turn the fork, and the riderhandle in the second mode, may be configured to be rotationallyuncoupled from the stem, preventing forces on the rider handle fromturning the fork. Rotational coupling and decoupling of the rider handlefrom the fork may be accomplished in numerous mechanical ways, and theinvention, in its broadest sense, is not limited to any particularmechanical interconnection. Rather, any manner in which the rider handlemay be coupled and uncoupled to the fork is considered to fall withinthe scope and spirit of the invention. Moreover, the location of acoupling decoupling mechanism is not necessarily critical to embodimentsof the invention. It may be located between a rider handle assembly anda stem, or it may be located between a stem and a fork.

Thus, by way of example only, the coupling mechanism 202 may, in a firstmode, permit mechanical interconnection between the rider handle and thefork such that when a tricycle rider applies a turning force to therider handle, the turning force is conveyed to the front wheel via thefork. In a second mode, the coupling mechanism 202 may decouple therider handle from the fork in a manner permitting the rider handle toturn freely without conveying turning forces to the fork. This may beaccomplished, for example, by permitting selective coupling anddecoupling of the rider handle from the stem. (e.g., selective couplingand decoupling of rider handle assembly 200 and stem 305).

Thus, the term “couple”, “coupling”, “coupling mechanism” and“rotational engageable” are meant herein to include any mechanicalengagement which transfers the rotation of one part to the other coupledpart, by causing it to rotate similarly.

When, in a first exemplary mode of operation the steering of tricycle800 is accomplished using rider handle assembly 200, i.e. the turning,e.g. left or right, of rider handle assembly 200 turns the fork 130which turns the front wheel 100, the rider may assume control ofsteering while simultaneously propelling the tricycle 800 using thepedals 141 and 142. If when the rider is in control in the first mode, aperson walking behind the tricycle tries to push the tricycle frombehind using parental handle 500, the rider may prevent the personwalking behind from assuming control. Thus the rider handle may bemechanically disconnected from the stem. When this occurs, the riderhandle may cease to function as a steering mechanism and may simplyfunction as support that the rider may grasp for balance or in order topermit a child to pretend to steer. In this circumstance, the riderhandle may lock in a stationary position rotationally disconnected fromthe fork and front wheel, or may rotate freely within a range of motionindependent of the fork and the front wheel.

There are many differing ways in which a handle assembly may berotatably coupled and decoupled from a fork or fork stem. The examplesprovided in this specification are not intended to limit the inventionto any particular example. Other coupling and decoupling mechanisms maybe used such as a detent, a pin, a screw connector, or any otherconnectors. One example, illustrated in FIG. 5 c involves an engageableand disengageable coupling. For example, a coupling member 204associated with the rider handle assembly 200 may include a surface thatselectively mates with an extension of the stem. As illustrated in FIG.5 c, for example, a shaped end 308 of stem 305 is selectively mateablewith a corresponding shaped slot 307 of coupling member 204. When theshaped end 308 is seated in slot 307, force exerted on the rider handleassembly 200 is capable of turning the stem 305, and consequently fork133 and wheel 100. When the shaped end 308 is decoupled from slot 307 ofcoupling member 204, the rider handle assembly 200 may be incapable ofturning the wheel 100.

The stem's top end 308, in this example, has an almost rectangularshape, although for most of its length the fork stein 305 is round. Theopening 307, depicted in silhouette since the opening 307 is hidden fromthis view point, has a corresponding shape thereto. Hence, while beinginserted into the opening, the fork stem 305 is affixed, i.e. it cannotrotate, inside the second coupling member 204. In one embodiment, theuse a symmetrical shape for the stem's top 308 allows the inserting ofthe fork stem in two ways, one way for allowing the front wheel axis tolead the stem axis in a first mode of operation, and another way forallowing the front wheel axis to trail the stem axis in the second modeof operation. Moreover, the almost rectangular shape is non-limiting andmany other, non-round shapes can be used for the purpose of affixing thefork stem 305 inside the second coupling member's opening 307.

As illustrated in FIG. 5 b, a knob 810, or any other manuallyactivatable release mechanism, which may be a part of the couplingmechanism 202, may be used for coupling the handle arm 201 to the fork'sstem 305. Specifically, and as described later in greater detail, whenknob 810 is lifted, decoupling occurs, and when it is moved downwardonto stem 305, coupling occurs. Thus, in a first mode, rider handleassembly 200 is rotationally engageable with the fork's stem 305 in amanner permitting a tricycle rider to exert forces on the rider handle200 and thereby turn the fork. On the other hand, the rider handle 200in the second mode, may be rotationally disengageable from the fork'sstem 305 for preventing forces on the handle from turning the fork.Examples of other structures that may be used to selectively couple ahandle to a stem include protruding spring-biased pins that can bedepressed to decouple and which can snap back into place to couple; orusing the pin 309 without part 810 for coupling and decoupling the ridehandle 200 to the stem 305, as described in relations to FIG. 7, etc. .. . .

FIG. 5 b is a cross-sectional view of a part of the coupling mechanism202, according to one embodiment of the invention. The mechanism 202allows coupling of the handle arm 201 and the fork stem 305. Three mainmembers are depicted in the diagram: a first coupling member 203, asecond coupling member 204 and a grasping member 810 (or a knob). Thefirst coupling member 203 is statically coupled to the handle arm 201,thereinside. In the middle of the first coupling member 203 there is ashaft through which the fork stem 305 can be inserted. The secondcoupling member 204 is positioned inside the top end of the firstcoupling member 203, being slideable up and down. In the bottom of thesecond coupling member 204 there is an opening 307 into which the topend 308 of the fork stem 305 may fit. When the second coupling member204 is in its upper position, it is disengaged from the fork stem 305.When the second coupling member 204 slides down, the fork stem 305 isinserted into the opening 307, and a coupling is achieved between thesecond coupling member 204 and the fork stem 305, and hence also betweenthe steering arm 201 and the fork stem 305. In order to affix the forkstem 305 inside the second coupling member's 204 opening, the fork stem305 has a non-round shape in its top end and the opening has acorresponding shape thereto, as illustrated in a non-limiting way. Thegrasping member 810 is, on one hand, external to the handle arm's tube201 and on the other hand internal and connected to the second couplingmember 204, by a connecting element 309 such as a pin, a screw, or anyother element. Thus by sliding the grasping member 810 up and down, thesecond coupling member 204 also slides up and down as well. Moreover,the grasping member 810 as depicted in the diagram provides theindividual using it a better grip and easier control on the secondcoupling member's 204 position (whether up or down). However, in otherembodiments the grasping member 810 is redundant or not required, andthen, the connecting element 309 alone may be used as a third couplingmember, as described in relations to FIG. 7. The connecting element 309has been depicted as a single element, such as pin etc. connecting bothsides of the third coupling grasping member 810 via the handle arm 201and the second coupling member 204. This is not mandatory though and inother embodiments other solutions can be applied instead. For example,by having a third coupling member composed of two parts (e.g., a “rightpart” and a “left part”), a short pin can be coupled to each part, whilethe short pin can penetrate the steering arm and form the connectionwith the second coupling member, whereas, in another embodiment, the twoparts may be connected by a spring. In one embodiment second couplingmember 204 may be designed from two interconnecting parts each made froma different material.

In one embodiment, the coupling mechanism 202 may be in the front tube707 of the frame 700. In other embodiments, the coupling mechanism mayappear on top of the front tube 707. In other embodiments, the couplingmechanism may appear below the front tube 707.

FIG. 6 is a cross-sectional view of the handle arm 201 holding the firstcoupling member 203, according to one embodiment of the invention. Asdepicted in the diagram, the first coupling member 203 is held bygrasping elements 610, such as snaps, in the handle arm's tube 201. Inthe presently illustrated example, there are two snaps holding the firstcoupling element, one of each side, yet this in non-limiting and anyother number of snaps can be used, as long as the first coupling memberis affixed within the steering arm's tube. The shaft 306 is the shaft inwhich the fork stem may slide in. These figures though are non-limiting,and other coupling mechanisms may be used and other alternatives mayexist.

FIG. 7 is a cross-sectional side view of the second coupling member 204inside the first coupling member 203, according to one embodiment of theinvention. In the handle arm's tube 201 there are grooves 713. Throughthese grooves a guiding element 714, connected to the second couplingmember 204, can slide up and down, thus lifting and lowering,respectively, the second coupling member 204. The second coupling member204 should stay in a low, down position when coupled to the pivot, andin an upper, high position when disconnected therefrom, a lockingmechanism is described. According to one embodiment, this lockingmechanism comprises protrusions 716 in the groove 713. When the guidingelement crosses a protrusion 716, it is locked therebehind. In order toallow crossing of the guiding element, the protrusion should be made ofa flexible or resilient material. In addition, if the steering arm ismade of a non-flexible material, it is possible to attach theretoanother layer of a flexible material, either from the inside or from theoutside, forming the protrusion in this flexible layer. In the presentembodiment, the first coupling member 203, which is attached to thehandle tube 201 from the inside, can form this layer. Hence, asillustrated in the diagram, grooves are seen also in the first couplingmember 203, wherein the protrusions 716 are implemented therein. This isnon-limiting though and instead of using the first coupling member asthe flexible layer, other solutions may be provided as a dedicated pieceof flexible material which is attached to the handle arm's tube instead.Yet other embodiments may use other solutions, alternative to theprotrusions, such as using a screw as the guiding element, screwing itin the position where it needs to be locked.

In those cases when the coupling mechanism includes a knob, such aselement 810, as described with reference to FIG. 5 b, the guidingelement may form also the connecting element 309. Alternatively, theremay exist a connecting element 309, which is additional to the guidingelement. In one embodiment the guiding member alone may be the knob usedfor coupling and/or decoupling.

FIG. 8 illustrates the knob 810, according to one embodiment of theinvention. As was noted above, in one embodiment, the connecting element309 is able to slide up and down in the groove.

FIG. 9 a is a cross-sectional side view of the coupling mechanism in theuncoupled position. It can be seen, from looking at FIG. 9 a that thetop end of the fork stem 305 is free, that is, it is not inserted intothe opening 307 of the second coupling member 204. FIG. 9 b is across-sectional side view of the coupling mechanism in the coupledposition. In FIG. 9 b, illustrating the coupled position, the top end ofthe pivot is inserted into the opening 307. In each one of the positionsdescribed with reference to FIGS. 9 a and 9 b, the fork stem 305 isrotatably held in the first coupling member 203. In order to keep thefork stem 305 held in the first coupling member 203, the fork stem 305has an indentation 910. The indentation may include, for example, agroove that fully or partially circumscribes the stem 305, or it mayinclude a confined recess in the stem 305. A locking member 911 having aspring 912, clenching the pivot's indentation, may prevent it fromsliding out and releasing therefrom. Therefore, the locking member 911may prevent the fork stem 305 from releasing from the couplingmechanism.

FIG. 10 is a perspective view of the holding mechanism for engaging thefork stem 305, according to one embodiment of the invention. The lockingmember 911, in this case, has an oval opening 1010 through which thehead of fork stem 305 can pass, and one or more springs 912. The lockingmember 911 has a first side 1011 and a second side 1012. It is notedthough that the locking member is not necessarily rectangular and it maynot have definable sides. However, in order to explain the affixingmechanism, the embodiment illustrated is nearly rectangular in shape.When inserted into the handle tube, or into the first coupling member,the spring/springs 912 push the locking member 911 towards its 1011side, against the tube's wall. Upon inserting the fork stem 305 (seeFIG. 9 a), into the shaft 306 (see FIG. 6) of the first coupling member,the fork stem 305 reaches the locking member 911. Then, the top of thestem's end pushes the locking mechanism 911 towards its 1012 side. Whenthe stem's indentation reaches the locking mechanism 911, thespring/springs 912 are slightly released and push the mechanism into theindentation, thus affixing the fork stem 305 in correspondence to thelocking mechanism 911 and hence also in correspondence with the firstcoupling member. The mechanism illustrated in FIG. 10 is non-limitingand many other one-time locking mechanisms known per se may be usedalternatively, as applicable.

Embodiments of the invention may also include one or more rotationrestrictors. These rotation restrictors may restrict the front wheel toa certain angle. For example, in the first mode, where the front wheelaxis may lead the fork axis, the front wheel may be restricted to anangle D (See FIG. 21) of between 70°-100° in order to prevent the frontwheel, or the rider handle, from hurting the rider while riding. Inanother embodiment, the front wheel may be restricted to an angle ofbetween 50°-150°. In another example, in the second mode, where thefront wheel axis may trail the fork axis, the front wheel may berestricted to an angle of between 70°-100° in order to prevent the frontwheel from turning to a position where the front wheel axis leads thefork axis during travel. In another embodiment the front wheel may berestricted to an angle of between 50°-179°. As used herein, “a rotationrestrictor for preventing” includes any structure capable of restrictingthe rotational movement of the front wheel, regardless of whether therestrictor completely prevents rotation past a certain point, or whetherthe restrictor only prevents rotation past a certain point when forcesexerted are below a threshold (e.g., the restrictor may exert a biasforce that may be overcome by an opposing force greater than the biasforce.) In either instance, rotation restrictors consistent withembodiments of the invention may be used to maintain the front wheel ina certain temporal orientation whether the front wheel axis leads thefork axis or whether the front wheel axis trails the fork axis.

In one embodiment the rider handle angle is restricted due to safetyconsiderations, protecting the body of the rider from being hit by therider handle. In one embodiment the turning angle of the rider handlemay be between 80° and 100°. In one embodiment the turning angle of therider handle may be around 90°. In one embodiment the turning angle ofthe rider handle may be between 20° and 170°.

With such configurations, in some embodiments, the front wheel of atricycle may be maintained in one of two positions, according to firstand second modes of operation. In a first mode of operation, the wheelaxis may lead the stem axis and in a second mode of operation, the frontwheel may be rotated backwards and maintained in a position where thestem axis leads the front wheel axis. Thus, in some embodiments, all aparent need do to take over steering control is to disengage the riderhandle from the front wheel and turn the front wheel backwards. In oneembodiment the rotating factor of the pedal rod may be disengaged fromthe rotating factor of the front wheel. In another embodiment the pedalsmay be folded as well. Similarly, if a parent is pushing the tricycle,and desires to turn steering control over to the rider, all the parentneed to do, in this embodiment, is to turn the front wheel to the frontand couple the rider handle to the front wheel. In one embodiment therotating factor of the pedal rod may be engaged to the rotating factorof the front wheel. In another embodiment the pedals may be unfolded aswell.

Depending on the embodiment, the tricycle may provide an option ofchanging pedal position between modes of operation. In one embodiment afootrest 300 (see FIG. 2) may be connected to the main frame 700 forallowing the rider to rest his feet on the footrest 300 while thetricycle 810 is being pushed from behind. In one embodiment the footrest300 is foldable, and it may be folded backwards under the chair 600 orit may be folded in any other way. In one embodiment the pedal rod 140propelling factor may be disengaged from the rotating factor of thewheel 102, effectively allowing the pedals to stay static while thetricycle 810 is being pushed. The method for engaging and disengagingthe pedal rod propelling factor and the rotating factor of the wheel isknown in the art. In the second mode of operation the rider handle 200may be uncoupled from the fork 130, effectively allowing an individualto push the tricycle 810 from behind and steer it using the parentalhandle 500 while the rider sits on the chair 600, rests his feet on thefoot rest 300 and rests his hands on the rider handle 200. Meaning thatin this second mode of operation, the steering of the tricycle 810 doesnot have to interfere with the rider's hands holding the rider handle200. Nevertheless, the tricycle 810 may be changed to the first mode ofoperation by coupling the fork 130 with the rider handle 200, optionallydetaching the parental handle 500, optionally folding the footrest 300,and optionally reengaging the pedal rod 140 to the front wheel 102. Thusin the first mode of operation the rider can propel the tricycle 810 byhimself using the pedal rod 140 and steer the tricycle 810 by himselfusing rider handle 200.

FIG. 11 is a perspective view of a tricycle, having a swivel wheel,according to another embodiment of the invention. The tricycle mayinclude a frame a105, a steering assembly a107, a front tube a106, whichmay be attached to the frame a105, and which pivotally holds the riderhandle's a115 arm, a supporting structure a207, and a pressuretransferring element a208 which is shown in its forward placement. Thewheel assembly a108 includes a front wheel a102, a mud-shield a301, apedal a116 and shock suspension a117, where, in the first mode ofoperation, the front wheel a102 may be steered by the steering assemblya107. In one embodiment, the supporting structure a207 and themud-shield a301 may be made from one piece, however alternatives mayexist, for example, the supporting structure a207 may be joined ordisjoined from the mud-shield a301, using snap-ins, screws, or any otheradjoining techniques. Two rear wheels such as rear wheel a104 may belocated respectively at the two sides of the back of the frame a105 androtatably held by the back of the frame a105. The frame a105 and thesteering assembly a107, the wheel assembly a108 and the two rear wheels,may constitute the body of the tricycle vehicle, according to anembodiment. The tricycle vehicle may also include one or more of thefollowing: a seat a110 which may be assembled and disassembled, afoldable leg support mechanism a119, a handle a112 which enables anexternal control of the tricycle vehicle, and a basket a702.Furthermore, the tricycle may also include an enclosure a1201 attachedto the front tube a106 for protecting the steering assembly a107, andfor other purposes as well.

FIG. 12 is a partial assembly view of the tricycle of FIG. 11, having aswivel wheel, where the enclosure a1201, is omitted. The rider handlea115 may include a rail a1151 and a vertical bar a1152, which extendsfrom the center of the rail a1151 downwards. A hole a1153 may beconfigured on the vertical bar a1152, and on the lower end of thevertical bar a1152 a notch a1154 may be configured. Inside the bottom ofthe front tube a106 may be configured a rotation restricting mechanisma712. The tricycle vehicle may include a mechanism a202, for couplingand decoupling the handle bar a115 and the wheel assembly a108. In anembodiment, a turning sign a3011 may be located on the mud-shield a301for indicating the front wheel's assembly a108 direction. The directionof the front wheel's assembly a108 may be changed by pressing thepressure transferring element a208 and switching the front wheel'sdirection.

FIG. 13 is an enlarged perspective view of an assembly offront tubea106, according to an embodiment of the invention. On the top end of thefront tube a106 two notches a1061 may be located which are correspondingto the two notches a1062 (one notch a1062 is hidden) on the lower end ofthe front tube a106. On the lower part of the front tube a106 twoopening a1063 (one of the openings is hidden from view) may be located,on the upper part of the front tube a106 two openings a1064 may belocated as well, where the four opening a1063 and a1064 may beseparately located on the position of ¼ of a circle from the two notchesa1061, and a1062 respectively. The notches a1061 and the opening a1064may be configured for assisting in the assembly of the enclosure a1201.The notches a1062 and the opening a1063 may be configured for assistingin the assembly of the rotation restricting mechanism a712. The rotationrestricting mechanism a712 may comprise the base a7121 and a shaft a7122which extends upwards from the base a7121, on the upper part of theshaft a7122 two snaps a7123 may be configured, and on the lower part ofthe base two protrusions a7124 (one protrusion may be hidden) may beconfigured. While the shaft a7122 may be inserted into the front tubea106, the snaps a7123 correspond to the opening a1063 and lockingtherein, the protrusion a7124 may slide into the notches a1062 whichhave a corresponding shape thereto.

FIG. 14 is another enlarged perspective view front tube a106 and itsinterconnecting base a7121, according to an embodiment of the invention.The base a7121 and the shaft a7122 are round shaped, and both are hollowin the middle the base having a hole a7125. On bottom of the base a7121facing down are configured two non-continuing grooves, or recessedmembers, a7126 and a7127, where each has the form of an arch having twoends, substantially in the perimeter of the front tube a106. The twogrooves (recessed members) a7126 and a7127 may be allocated on opposingsides from each other. In one embodiment, the grooves a7126 and a7127may be formed together with the base a7121. Alternatives may be used aswell, for example, the base a7121 may be composed from two pieces, andeach groove may be configured on one of the parts of the base.

FIG. 15 is a perspective assembly view of a front wheel assembly,according to an embodiment of the invention. The wheel assembly a108 mayinclude a fork a304 which may be affixed to two ends of the axle of thefront wheel, and a stem a305 attached to the top of the fork a304. Thefork a304 may have a hole a3041 for assisting the placement of mudguarda301. On the top end of the stem a305 an indentation a3052 may belocated. The part a202 may be formed of two parts a203 and a204, wherethe part a202 may be connected to the stem a305. The supportingstructure a207 and mud-shield a301 may be made of one piece using theinjection method or any other known method. Alternatively, otherembodiments may be used. For example, the support structure a207 may beaffixed to the mudguard a301. The support structure a207 may include acone extending from the top of the mud-guard a301. The cone may have acenter hole a2071 on the top part of the cone, for the stem a305 toslide through therein, and on the side of the cone a cavity a2072 may beconfigured to allow a guide element to slide through. The pressuretransferring element a208 may include a connector lever a2081, twopositional columns a2083 extending down which are on two ends of the ofconnector lever, and two springs a2084 may be affixed under the twopositional column a2083, for pushing upwards the guide element a2082,which is formed from one of the positional column a2083 extensions.

FIG. 16 is another assembly view of the front wheel assembly, accordingto an embodiment of the invention. The coupling part a202 may comprise abase a2021, a shaft a2022 extended upwards from the base a2021, and abearing a2023 affixed inside of the base a2021. The base a2021 may havea restricting mechanism, which may be formed of a lock hole a2024 and alock groove a2025, where the positional column a2082 may be insertedinto either the lock hole a2024 or the lock groove a2025. The supportingstructure a207 may have a grasping element in order to affix thesupporting structure a207 to the fork a304. The grasping element mayconstitute two sets of side walls a2075 which are extending down, and across wall a2076 connecting two side walls of each set. The bottom shapeof each set of side walls a2075 and cross walls a2076 are correspondingto the top shape of the of the fork a304, the grasping elementconfigured a positional column a2077 extending down which may beinserted into the hole a3041 (see FIG. 15) of the fork a304 in order toassemble the support structure a207 and fork a304 together.

FIG. 17 is a schematic diagram of an exploded view of coupling parta202, according to an embodiment of the invention. The coupling parta202 may have a shaft a306 configured for the stem a305 to slidethrough. On the upper part of the shaft a2022 of the coupling part aprojection locking mechanism may be configured. The locking mechanismmay include locking elements a2028 and a spring a2029. The shaft a2022may have two holes a2027, where the two locking element a2028 mayproject out of the holes a2027 by applying the spring a2029 to pressurethe two locking elements a2028 from inside the shaft a2022 out. Otherlocking mechanisms may be used as well. The protrusion a2026 on thelower part of the shaft a2022 is configured to correspond to the notcha1154 (see FIG. 12) configured at bottom of the vertical tube a1152 forattaching the coupling part a202 to the steering arm a115.

FIG. 19 depicts a partial cut away view of the region circled in FIG.18. Specifically, FIG. 19 depicts a cross-sectional view of the shafta2022 and the coupling mechanism used to connect the vertical tube a1152of the steering arm a115 and the shaft a2022, according to oneembodiment. In this embodiment, the two locking elements a2028projecting out of the two holes a1153 (See FIG. 12) and are configuredto hold on vertical bar a1152, in order to assemble the coupling parta2022 and the vertical tube a1152 of steering arm a115 in alignment toeach other. In the upper part, of coupling part a2022, a projectiona3061, which extends inside, engages indentation a3052 on the upper endof the stem a305, for the coupling the coupling part a2022 to the stema305. The base a2021 of the coupling part a2022 may be stationed betweenthe top of supporting structure a207 and the bottom of the restrictingmechanism a7121.

In one embodiment, the hole a2024 (see FIG. 17) on the base a2021 ofcoupling part a2022 may correspond to the center of the recessed membera7126 (see FIG. 14) of the rotation restricting mechanism a712, wherethe groove a2025 may correspond to the recessed member a7127 of therotation-restricting mechanism a712. Therefore, when in the first mode,i.e. the rider-steerable mode, the connector lever a2081 of the pressuretransferring element a208 may face front, and the guide a2082 (see FIG.15) may be inserted in the hole a2024 of the coupling mechanism a202 andinserted in the recessed member a7126. In this configuration the raila1151 of steering arm a115 is essentially coupled with the supportingstructure a207 which is connected to the front wheel assembly a108, thusenabling the rider to steer the tricycle.

The rotating angle of the steering arm a115, in the first mode, may belimited to the length and curve of the recessed member a7126. In otherwords, the maximum angle of the steering arm a115 turning may correspondto the curve of the recessed member a7126. For example, if the curve ofthe recessed member a7126 is 90°, and the hole a2024 of the couplingpart a202 corresponds to the center of the recessed member a7126, themaximum angle of the steering arm a115 rotation may be limited to 45°left or 45° right. If, on the other hand, the curve of the recessedmember a7126 is 60°, the maximum angle of the steering arm a115 rotationmay be limited to 30° left or 30° right. The steering arm a115 anglerestriction may be set at other angles which for example provide easysteering while protecting the rider. Other embodiment, other solutions,other angles or any other mechanisms may be applied without exceedingthe scope of the invention.

In one embodiment, the tricycle may be transferred to its second mode bypressing down the connector lever a2081 of the pressure transferringelement a208, the guide a2082 may be released from the recessed membera7126 and the hole a2024, and the wheel assembly a108 may be turned, inan angle greater than the limiting angle of recessed member a7126,thereby transferring the tricycle vehicle from the first mode ofoperation to the second mode of operation.

FIGS. 20, 21 and 22, depict the tricycle in its second mode, accordingto an embodiment of the invention. The connector lever a2081 of thepressure transferring element a208 may be located near the rear part ofthe head tube, i.e. the connector lever is faced back, and the guidea2082 may be inserted into the groove a2025 of the coupling part a202and inserted into the recessed member a7127. In this position the raila1151 of the steering arm a115 is not coupled with the wheel assemblya108 and therefore forces, i.e. the turning left or right, exerted onthe rider handle do not substantially affect turning of the front wheel.In an embodiment, the angle of rail a1151 turning is limited to (thecurve of) two ends of the recessed member a1727. This is due to themaximum angle of the curve of the recessed member a7127. For example, ifthe curve of the recessed member a7127 is 90°, and the groove a2025 ofcoupling mechanism a202 corresponds to the recessed member a7127, thesteering arm a115 maximum turning angle is 45° to the left or to theright. In another example, if the curve of the recessed member a7127 is60°, the steering arm a115 maximum turning angle is 30° to left or tothe right. Other embodiments, and other angles of the recessed member7127 may be applied. Furthermore, the recessed members a7126 and a7127need not necessarily have the same carved angle, alternatives may exist,where they may have different curved angles, for example, recessedmember a7126 may be 90° where recessed member a7127 may be 60°, etc.

By pressing down the connector lever a2081 of the pressure transferringelement, the guide a2082 may be released from the recessed member a7127and the groove a2025, and the wheel assembly may be turned in an anglegreater than the limiting angle of recessed member a7127, therebytransferring the tricycle vehicle from the second mode of operation tothe first mode of operation.

As described before, there is an offset from the central axis of thestem a305 and the horizontal axle a118 of the front wheel. The offsetmay be located near the front of the head tube, i.e. faced front, whilethe guide a2082 is placed in recessed member a7126 via the hole a2044,where the distance from rear wheel axle to front wheel axle may beapproximated at 480 mm; whereas the offset may be faced back while theguide a2082 is placed into recessed member a7127 via the groove a2045,and the distance from the rear wheel axle to the front wheel axle may beapproximated at 440 mm. When in the first mode of operation, thedistance from rear wheel axle to front wheel axle may be typicallylonger than when in the second mode of operation.

FIGS. 23 and 24 are views of a suspension mechanism, according to anembodiment of the invention. The suspension mechanism a117 may include abottom cover a1171, a body a1172 and an upper cover a1173. The bottomcover a1171 may be affixed to the body a1172 using screws snap-ins orany other method, where the upper cover a1173 may be placed or attachedto the body a1172. The bottom cover a1173 and the lower part of bodya1172 are configured such that the axle a118 of the front wheel a102 maybe positioned in the buffer slot a1174.

FIG. 25 is a diagram bottom up view of the front wheel and its pedals,according to an embodiment of the invention. The front wheel may have aclutch mechanism a119 for coupling/decoupling the pedals a116, and theirpedal rod, to the rotation factor of the horizontal axle a118 of thefront wheel a102. When the axle a118 is decoupled from the pedals a116and their rod, the pedaling will not rotate the front wheel. When therotation factor of the horizontal axle a118 is coupled to the pedalsa116 and their rod, the rider may pedal the pedals a116 and rotate thefront wheel a102. Hence, when the vehicle is in its first mode, the axlea118 and the pedal a116 are typically coupled by the clutch, whereaswhen the vehicle is in its second mode, the axle a118 is typicallydecoupled from the pedal a116 by the clutch.

FIG. 26 is a partial cut-away view of the suspension mechanism a117,according to an embodiment of the invention. The suspension mechanisma117 may include a member a1175, configured to pivotally hold the pedalrod of the front wheel a102, and a spring a1178, attached to the membera1175, for exerting a pushing force on the member a1175. In the lowerpart of the coupling member a1175, a groove a1176 is configured whichcorresponds to the shape of the pedal rod of the front wheel a102. Onthe upper part of the member a1175, a pillar a1177 may be configuredhaving a radius slightly smaller than the radius of the spring a1178 foraffixing the spring a1178 over member a1175. The body a1172 may beaffixed to the fork a304 by a bolt a1179, or any other known mechanism.

In other embodiments, the pillar a1177 may not exist, instead, theelement a1175 may have a chamber structure, on two opposite side of themember a1175 where configured guiding grooves, and two guiding trailsmay be configured inside of the body a1172 to correspond to the grooves.

FIG. 27 is a detailed view of a portion of the front wheel assembly,according to another embodiment of the invention. Similarly to thedescribed in relations to FIG. 15, the wheel assembly may comprise afork 3040 and a mudguard 3010 with a supporting structure 2070. Thesupporting structure 2070 and mud-shield 3010 may be made of one pieceusing the injection method or any other known method. Alternatively,other embodiments may be used. For example, the support structure 2070may be affixed to the mudguard 3010. The support structure 2070 mayinclude a cone extending from the top of the mudguard 3010. The frontwheel assembly may be held and restricted by the parts 2020, 7120, and1060, which may function similarly to parts a2021, a7121, and a106respectively as described in relations to FIGS. 13-15. In thisembodiment the pressure transferring element 2080 may be a button whichextends from the side of the mudguard, and may be pressed for turningthe front wheel from the configuration where the stem axis leads thefront wheel axis to a configuration where the stem axis trails the frontwheel axis or vise-versa, e.g. when the tricycle is transferred from itsfirst mode of operation to its second mode of operation. Once the frontwheel has been turned the pressure transferring element 2080 may bereleased where it can slide into one of the grooves as described inrelations to FIG. 16.

FIGS. 28, 29, 30 and 31 are further detailed views of a front wheelassembly, according to an embodiment of the invention. FIG. 28 depictsthe front wheel assembly of FIG. 27 with the head tube 1060 omitted.Similarly, FIG. 29 depicts the front wheel assembly of FIG. 28 with therestricting element 7120 omitted. FIG. 30 depicts the front wheelassembly of FIG. 29 with the rail 1150 of the rider handle omitted.Similarly, FIG. 31 depicts the front wheel assembly of FIG. 30 with thecoupling part 2040 omitted. As depicted, the stem 3050 which isconnected to the fork 3040 may slide through the hole of supportingstructure 2070.

FIG. 32 is yet a further detailed view of the front wheel assembly,according to an embodiment of the invention. FIG. 32 depicts the frontwheel assembly of FIG. 31 with the support structure 2070 and mudguard3010 omitted. As depicted the pressure transferring element 2080 may beheld by the spring 2089 and may be affixed under the pressuretransferring element 2080 for pushing upwards the pressure transferringelement 2080, thereby restricting the turning angle of the front wheel.In an embodiment, the pressure transferring element 2080 is not fixed inits place by any connecting technique, such as screws or glue, but isheld in place by spring 2089 which presses it towards the top of thesupporting structure 2070.

While some embodiments of the invention have been described by way ofillustration, it will be apparent that the invention can be carried intopractice with many modifications, variations and adaptations, and withthe use of numerous equivalents or alternative solutions that are withinthe scope of persons skilled in the art, without departing from theinvention or exceeding the scope of claims.

What is claimed is:
 1. A tricycle operable between a first mode ofoperation steerable by a tricycle rider, and a second mode of operationsteerable by an individual pushing the tricycle, the tricyclecomprising: a pair of rear wheels; a front wheel having opposing sidesand a front wheel axis; a head tube; a frame configured to rotatablysupport the rear wheels and configured to support the head tube at adistance from the rear wheels; a pair of pedals, each pedal configuredfor connection about the front wheel axis to rotate the front wheel; afork having at least one blade configured to support the front wheel ina manner permitting the front wheel to rotate about the front wheelaxis; a stem configured to extend from the head tube in a mannerpermitting the stem to rotate, the stem including a metal rod having aminimum diameter that is at least three times smaller than a width ofthe front wheel; a rider handle, configured to turn the fork about astem axis extending transverse to the front wheel axis, the rider handlein the first mode, where the stem axis trails the front wheel axis,being configured to be rotationally coupled with the stem in a mannerpermitting a tricycle rider to exert forces on the rider handle andthereby turn the fork, and the rider handle in the second mode, wherethe stem axis leads the front wheel axis, being configured to berotationally uncoupled from the stem, preventing forces on the riderhandle from turning the fork and permitting the individual pushing thetricycle to turn the fork via a pushing force; and wherein the stemextends from the fork at an angle of between about 165 degrees and 179degrees and wherein an offset distance between the stem axis and thefront wheel axis is between 15 mm and 40 mm.
 2. The tricycle of claim 1,wherein the fork includes two blades configured to rotatably support thefront wheel therebetween.
 3. The tricycle of claim 1, wherein the riderhandle is configured to be uncoupled from the stem via a manuallyactivatable release mechanism.
 4. The tricycle of claim 3, wherein therider handle is configured to be coupled to the stem via a snap-in-placemechanism.
 5. The tricycle of claim 1, further comprising a couplingmechanism associated with the stem, for permitting an operator toselectively couple and uncouple a rotational connection between therider handle and the stem.
 6. The tricycle of claim 5, wherein thecoupling mechanism is configured such that in the second mode, the riderhandle is freely rotatable independent of the stem, and in the firstmode the rider handle is locked to the stem for rotation with the stem.7. The tricycle of claim 1, wherein the metal rod that has a minimumdiameter that is at least four times smaller than the width of the frontwheel.
 8. The tricycle of claim 1, further including a parental handleextending from a rear portion of the tricycle and permitting thetricycle to be pushed and steered from behind.
 9. A tricycle operablebetween a first mode of operation steerable by a tricycle rider, and asecond mode of operation steerable by an individual pushing thetricycle, the tricycle comprising: a pair of rear wheels; a front wheelhaving opposing sides and a front wheel axis; a head tube; a seat; aframe configured to support the seat, to rotatably support the rearwheels and to support the head tube at a fixed, non-adjustable distancefrom the rear wheels; a fork having at least one blade configured tosupport the front wheel in a manner permitting the front wheel to rotateabout the front wheel axis; a stem configured to rotatably extend fromthe head tube; a rider handle, configured to turn the fork about a stemaxis transverse to the front wheel axis, the rider handle, in the firstmode, where the stem axis trails the front wheel axis, being configuredto be rotationally coupled with the stem in a manner permitting atricycle rider to exert forces on the rider handle and thereby turn thefork, and the rider handle in the second mode, where the stem axis leadsthe front wheel axis, being configured to be rotationally uncoupled fromthe stem, preventing forces on the rider handle from turning the forkand permitting the individual pushing the tricycle to turn the fork viapushing force.
 10. The tricycle of claim 9, wherein the stem extendsfrom the fork at an angle of between about 165 degrees and 179 degrees.11. The tricycle of claim 9, wherein an offset distance between the stemaxis and the front wheel axis is between 15 mm and 40 mm.
 12. Thetricycle of claim 9, wherein the stem has a minimum diameter that is atleast three times smaller than the width of the front wheel.
 13. Thetricycle of claim 9, wherein the stem has a minimum diameter that is atleast four times smaller than the width of the front wheel.
 14. Thetricycle of claim 9, wherein the handle is configured to be uncoupledfrom the stem via a manually activatable release mechanism.
 15. Thetricycle of claim 14, wherein the handle is configured to be coupled tothe stem via a snap-in-place mechanism.
 16. A tricycle operable betweena first mode of operation steerable by a tricycle rider, and a secondmode of operation steerable by an individual pushing the tricycle, thetricycle comprising: a pair of rear wheels; a front wheel havingopposing sides and a front wheel axis; a head tube; a frame configuredto rotatably support the rear wheels and configured to support the headtube; a fork having at least one blade configured to support the frontwheel in a manner permitting the front wheel to rotate about the frontwheel axis; a stem configured to extend from the head tube in a mannerpermitting the stem to rotate; a rider handle, configured to turn thefork about a stem axis extending transverse to the front wheel axis, therider handle in the first mode, where the stem axis trails the frontwheel axis, being configured to be rotationally coupled with the stem ina manner permitting a tricycle rider to exert forces on the rider handleand thereby turn the fork, and the rider handle in the second mode,where the stem axis leads the front wheel axis, being configured to berotationally uncoupled from the stem, preventing forces on the riderhandle from turning the fork and permitting the individual pushing thetricycle to turn the fork via pushing force; and wherein the stemextends from the fork at an angle of between about 165 degrees and 179degrees and wherein an offset distance between the stem axis and thefront wheel axis is between 15 mm and 40 mm.
 17. The tricycle of claim16, wherein the handle is configured to be uncoupled from the stem via amanually activatable release mechanism.
 18. The tricycle of claim 16,further comprising a coupling mechanism associated with the stem, forpermitting an operator to selectively couple and uncouple a rotationalconnection between the handle and the stem.
 19. The tricycle of claim18, wherein the coupling mechanism is configured such that in the secondmode, the rider handle is freely rotatable independent of the stem, andin the first mode the rider handle is locked to the stem for rotationwith the stem.
 20. The tricycle of claim 1, wherein the metal rod thathas a minimum diameter that is at least four times smaller than thewidth of the front wheel.
 21. The tricycle of claim 1, wherein thepedals are configured for selective rotational engagement and rotationaldisengagement from the front wheel, thereby allowing rotation of thefront wheel.
 22. The tricycle of claim 9, further including a pair ofpedals, each pedal configured for connection about the front wheel axisto rotate the front wheel.
 23. The tricycle of claim 22, wherein thepedals are configured for selective rotational engagement and rotationaldisengagement from the front wheel.
 24. The tricycle of claim 9, furtherincluding a footrest connected to the frame.
 25. A tricycle operablebetween a first mode of operation steerable by a tricycle rider, and asecond mode of operation steerable by an individual pushing thetricycle, the tricycle comprising: a pair of rear wheels; a front wheelhaving opposing sides and a front wheel axis; a head tube; a seat; aframe configured to support the seat, to rotatably support the rearwheels and to support the head tube at a distance from the rear wheels;a pair of pedals, each pedal configured for connection about the frontwheel axis to rotate the front wheel; a fork having at least one bladeconfigured to support the front wheel in a manner permitting the frontwheel to rotate about the front wheel axis; a stem configured torotatably extend from the head tube; a rider handle, configured to turnthe fork about a stem axis transverse to the front wheel axis, the riderhandle, in the first mode, where the stem axis trails the front wheelaxis, being configured to be rotationally coupled with the stem in amanner permitting a tricycle rider to exert forces on the rider handleand thereby turn the fork, and the rider handle in the second mode,where the stem axis leads the front wheel axis, being configured to berotationally uncoupled from the stem, preventing forces on the riderhandle from turning the fork and permitting the individual pushing thetricycle to turn the fork via pushing force; and wherein the stem isoriented with respect to the fork at an angle chosen so that when thestem axis trails the front wheel axis the pedals are oriented forpedaling by a rider without a need to alter a distance between the seatand the head tube.